Sleep Duration Calculator

Calculate the number of hours between when you go to bed and when you wake up, with automatic handling for overnight sleep.

Enter 24-hour time; for example 22.30 represents 10:18 PM (use decimal for minutes).
If you wake after midnight, just enter the morning time, such as 6.75 for 6:45 AM.

Estimates sleep duration only; actual rest quality varies.

Examples

  • Bed at 22.30, wake at 06.45 ⇒ 8.15 hours
  • Bed at 23.75, wake at 07.00 ⇒ 7.25 hours
  • Bed at 00.50, wake at 08.25 ⇒ 7.75 hours

FAQ

What format are the times?

Enter hours on a 24-hour clock from 0 to 23.

Does it handle overnight sleep?

Yes, the formula wraps past midnight automatically.

Can I enter decimals for minutes?

Use decimals to represent partial hours, like 7.5 for 7:30.

How do I convert the result to minutes?

Multiply the output by 60 or use our minutes-to-hours converter for a quick reference.

Does this account for awakenings during the night?

No. Break out multiple sleep segments and sum them manually if you have long periods awake in between.

Additional Information

  • The formula assumes a full 24-hour day, wrapping around midnight so overnight sleep is calculated automatically.
  • Sleep duration is only one piece of the puzzle—factors like sleep stages, environment, and consistency also matter.
  • Record your sleep times daily to build a trendline and spot changes caused by travel, stress, or caffeine.

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